Scryer ... or how F8 met Mighty SissySIT

[Dennis Hui]

damnit, ANOTHER!! I barely have time to enjoy the one(s) I just built, before the urge to build the latest kicks in

That THD

Those distortion spectrums look so pretty...
BTW, any idea what may be causing that spike at 6.5K for the 1W measurements?

 

[Zen Mod]

some glitch in my cables, leading from EMU1212 to interface box, same as nasty looking peak at 20KHz

well, 6.3mm plugs are called professional ........go figure

one day I'll repair that

edit: besides - remember that proto is made in Ikebana style, and there are several LED lights around, big ones

 

[potepuh]

Any particular reason for the +/-23VDC power supply? Intentionally backed off a bit from 24-25? Also, would ACP+ have enough cojones to drive this one (2087C variety)?

 

[Zen Mod]

@von Ah

rail - anything you read between 22Vdc and 25Vdc is nominally 24Vdc

simple - Pa is always showing 24Vdc as result of having 18Vac secondaries

in realm of small A Class amps, with common used diode bridges and filtering, in most case that's ending as 22V5 to 23Vdc rail, sorta 1.25 multiplication factor, when going to compute AC to DC

Donut on my T-Bed is having slightly more than 18Vac per secondary, thus the difference ...... irrelevant in entire story

 

[1543]

Well done👍. Clean 15 Watts with very nice harmonics. Keep us updated.

 

[Zen Mod]

can't be different ...... all of them blatant steal of Papacrumbs

 

[Samuel Jayaraj]

Can Scryer be made to work without NFB?

 

[Zen Mod]

everything is possible, even wooden stove

though, Scryer (F8) concept is hardly optimized for that

start changing it to avoid loop NFB, introduce local degenerations, try to keep direct coupling ..... you'll end with BA3 FE

 

[nicoch58]

can be done with sony vfet?

 

[ACnotDC]

I like this kind of distribution of harmonics too. What about the output impedance? Is it lower than 0R2 like F8?

 

[Zen Mod]

can be done with sony vfet?

not so practical reworking it for Sony; highish Ugs is complicating things, and Sony is Weakling comparing to Tokins - think effective part resistance and xconductance

I like this kind of distribution of harmonics too. What about the output impedance? Is it lower than 0R2 like F8?

I didn't bother to measure that

 

[Zen Mod]

 

[codyt]

Sold!

 

[sp33ls]

FOMO is real, especially when in the process of building a SissySIT lol.

But, I spose these are two very different sounding amps based on the THD. Sissy still being the sweetest sand amp? Scryer looks to be much more tidy. 🙂

 

[codyt]

I really like the sound of this style FE into a semisouth'd mu-follower. Bet it sounds sweeeet into a SIT DEF OS

 

[Plott]

Just waiting for the answer from Watanabe, and if it's positiv...

 

[Vunce]

oooww...
I see smd

 

[von Ah]

This is looking great. I will likely be waving my hands emphatically whenever Scryer boards are available.

 

[Zen Mod]

FOMO is real, especially when in the process of building a SissySIT lol.

But, I spose these are two very different sounding amps based on the THD. Sissy still being the sweetest sand amp? Scryer looks to be much more tidy. 🙂

same character, 2nd dominant, that's most important

what you get with autoformer gain/no loop NFB as most important virtue - say sort of organicity of sound, that not being substantially spoiled in my active FE amps, mostly due to applying Papabreadcrumbs

generally - I'm happy to enjoy both extremes of approach, say SissySIT (practically more THD Generator than amp) and say F4 (not having any substantial THD of its own)

all that because using speakers completely to my taste, and easy to drive

 

[Plott]

Well, yes, just ordered 2 THF51s 😀 So this will be the next one (after the M25)